Don Juan Pond was discovered in 1961 by George H. Meyer. It was named for two helicopter pilots, Lt. Don Roe and Lt. John Hickey, who piloted the helicopter involved with the first field party investigating the pond.[2]

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Don Juan Pond is a shallow, flat-bottom, hyper-saline pond. It has the highest total dissolved solids on record, with greater salinity than the Dead Sea or Lake Assal (Djibouti) (the same is true for Lake Vanda and perhaps other lakes in the McMurdo Dry Valleys). Salinity varies over time from 200 to 474 g/L, dominated by calcium chloride, and is over 18 times the ocean's salinity and 1.3 times that of the Dead Sea. It is the only Antarctic hypersaline lake that almost never freezes. It has been described as a groundwater discharge zone.[3] The area around Don Juan Pond is covered with sodium chloride and calcium chloride salts that have precipitated as the water evaporated.[4][5]

The area and volume of Don Juan Pond vary over time. According to the USGS topographical map published in 1977, the area was approximately 0.25 km2 (62 acres). However, in recent years the pond has shrunk considerably. The maximum depth in 1993–1994 was described as "a foot deep" (30 cm). In January 1997, it was approximately 10 centimetres (3.9 in) deep; [3] in December 1998 the pond was almost dry everywhere except for an area of a few tens of square metres. Most of the remaining water was in depressions around large boulders in the pond.[6]